Noise cancellation is the process of removing background noise from speech signal. The degradation of speech due to presence of background noise and several other noises cause difficulties in various signal processing tasks like speech recognition, speaker recognition, speaker verification etc. Many methods have been widely used to eliminate noise from speech signal like linear and nonlinear fi...

In this paper, we study the performance of the multiuser detection in a direct sequence optical code division multiple access (DS-OCDMA) system using novel periodic optical encoder applied to fiber-to-the-X (FTTX) passive optical network (PONs). The performance of our system is analyzed in a synchronous network using multilevel periodic codes (ML-PC) with a conventional receiver model and the r...

In this paper we study the effect of cancellation order on bit error rate (BER) performance of a Code Division Multiple Access (CDMA) system employing a linear Successive Interference Cancellation (SIC) receiver in both an Additive White Gaussian Noise (AWGN) channel and a Rayliegh fading channel. Four different ordering schemes are studied. We show that changing the cancellation order can lead...

In this paper, we present the development and evaluation of an integrated active noise control (ANC) communication headsets. This integrated system provides cancellation of noise that corrupted both the transmitted near-end speech and the received far-end speech. It utilizes an adaptive feedback ANC filter to reduce acoustic noise that corrupts the far-end signal inside the ear cups of headsets...

Speech enhancement is a long standing problem with numerous applications like teleconferencing, VoIP, hearing aids and speech recognition. The motivation behind this research work is to obtain a clean speech signal of higher quality by applying the optimal noise cancellation technique. Real-time adaptive filtering algorithms seem to be the best candidate among all categories of the speech enhan...

This paper presents and compares algorithms for combined acoustic echo cancellation and noise reduction for hands-free telephones. A structure is proposed, consisting of a conventional acoustic echo canceler and a frequency domain postfilter in the sending path of the hands-free system. The postfilter applies the spectral weighting technique and attenuates both the background noise and the resi...

We demonstrate a method to measure and actively reduce the coupling of vibrations to the phase noise of a cavity-stabilized laser. This method uses the vibration noise of the laboratory environment rather than active drive to perturb the optical cavity. The laser phase noise is measured via a beat note with a second unperturbed ultra-stable laser while the vibrations are measured by acceleromet...

Interference cancellation is widely used in a number of application such as acoustic and speech signal processing, data communication, biological signal acquisition etc. Many papers with different approaches have been reported to cancel interferences in biosignals. This paper provides a survey of existing methods for interference cancellation in ECG signal, FECG signal, EEG signal, and EMG sign...

Active noise cancellation (ANC) is the most important function in an audio device because it removes unwanted ambient noise. As many devices are increasingly equipped with digital signal processing (DSP) circuits, need for low-power and high-performance processors has arisen of hardware resource restrictions. Low-power design essential wireless have limited batteries. Noise cancellers process r...